Enhanced photocatalytic degradation of methylene blue on multiwalled carbon nanotubes-TiO2
Enhanced photocatalytic degradation of methylene blue on multiwalled carbon nanotubes-TiO2
复制标题
多壁碳纳米管-TiO2 上亚甲基蓝的增强光催化降解。
DOI：
10.1016/j.jcis.2013.02.017
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发表时间：
2013-05-15
影响因子：
9.9
通讯作者：
Wang, Xiangke
中科院分区：
文献类型：
--
作者：
Zhao, Donglin;Yang, Xin;Wang, Xiangke
采用两步法制备了纳米二氧化钛修饰多壁碳纳米管(MWCNT/TiO2光催化剂)，首先将TiO2光催化剂负载在MWCNT表面，然后在500℃的真空炉中将其晶化成锐钛矿型纳米晶，考察了其对亚甲基蓝的紫外光催化降解。MWCNT/TiO2能够在可见光范围内吸收大量的光能，有效地驱动光化学降解反应。在紫外光和可见光照射下，MWCNT/TiO2光催化剂(1：3)比纯TiO2光催化剂产生更多的中心点羟基自由基。在亚甲基蓝的光降解反应中，MWCNT/TiO2(1：3)的光降解反应速率明显高于裸TiO2光催化降解和MWCNTs/TiO2光催化降解亚甲基蓝。多壁碳纳米管可以从两个方面提高TiO2光催化活性，即e(-)的传输和吸附。本工作为制备高性能可见光催化剂MWCNT/TiO2光催化剂提供了新的思路，并为其在光催化降解有机物中的应用提供了新的思路。(C)2013 Elsevier Inc.保留所有权利。
A visible-light photocatalyst of multiwalled carbon nanotubes decorated with TiO2 nanoparticles (MWCNT/TiO2) was synthesized by a two-step method, in which TiO2 was first mounted on MWCNT surfaces by hydrolysis of tetrabutyl titanate and further crystallized into anatase nanocrystal in a vacuum furnace at 500 degrees C. The photocatalytic degradation of methylene blue over the ultraviolet (UV) and visible-light spectrum regions was investigated. The MWCNT/TiO2 was able to absorb a high amount of photo energy in the visible-light region, driving effectively photochemical degradation reactions. There were more center dot OH radicals produced by the MWCNT/TiO2 (1:3) than by pure TiO2 under UV and visible-light irradiation. In the photodegradation of methylene blue, as a model reaction, a signification enhancement in the reaction rate was observed with the MWCNT/TiO2 (1:3), compared to bare TiO2 and the physical mixture of MWCNTs and TiO2. MWCNTs can improve the photocatalytic activity of TiO2 in two aspects, namely e(-) transportation and adsorption. This work provides new insight into the fabrication of MWCNT/TiO2 as a high performance visible-light photocatalyst and facilitates its application in photocatalytic degradation of organic compounds. (C) 2013 Elsevier Inc. All rights reserved.